Re: [PATCH v4 03/10] scsi: ufs: Update the return value of supplier pm ops

[Can Guo <cang@codeaurora.org>]

On 2021-06-24 05:08, Bart Van Assche wrote:
> On 6/23/21 12:35 AM, Can Guo wrote:
>> rpm_get_suppliers() is returning an error only if the error is 
>> negative.
>> However, ufshcd_wl_resume() may return a positive error code, e.g., 
>> when
>> hibern8 or SSU cmd fails. Make the positive return value a negative 
>> error
>> code so that consumers are aware of any resume failure from their 
>> supplier.
>> Make the same change to ufshcd_wl_suspend() just to keep symmetry.
>> 
>> Signed-off-by: Can Guo <cang@codeaurora.org>
>> ---
>>  drivers/scsi/ufs/ufshcd.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>> 
>> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
>> index abe5f2d..ee70522 100644
>> --- a/drivers/scsi/ufs/ufshcd.c
>> +++ b/drivers/scsi/ufs/ufshcd.c
>> @@ -8922,7 +8922,7 @@ static int __ufshcd_wl_suspend(struct ufs_hba 
>> *hba, enum ufs_pm_op pm_op)
>>  		ufshcd_release(hba);
>>  	}
>>  	hba->wlu_pm_op_in_progress = false;
>> -	return ret;
>> +	return ret <= 0 ? ret : -EINVAL;
>>  }
>> 
>>  static int __ufshcd_wl_resume(struct ufs_hba *hba, enum ufs_pm_op 
>> pm_op)
>> @@ -9009,7 +9009,7 @@ static int __ufshcd_wl_resume(struct ufs_hba 
>> *hba, enum ufs_pm_op pm_op)
>>  	hba->clk_gating.is_suspended = false;
>>  	ufshcd_release(hba);
>>  	hba->wlu_pm_op_in_progress = false;
>> -	return ret;
>> +	return ret <= 0 ? ret : -EINVAL;
>>  }
> 
> I think the above patch shows that indicating failure by either
> returning a positive or a negative value is a booby trap. Please modify
> ufshcd_send_request_sense() and ufshcd_set_dev_pwr_mode() such that
> these return a value that is either zero or negative. Are there any
> other functions than that need to be modified?

Yes, there are more of them - both enter/exit_hibern8() and 
reset_and_restore()
can return positive values. I will modify all of them in next ver.

Thanks,

Can Guo.

> 
> Thanks,
> 
> Bart.